Electrical characterization of high k-dielectrics for 4H-SiC MIS devices
Journal article, 2019

We report promising results regarding the possible use of AlN or Al 2 O 3 as a gate dielectric in 4H-SiC MISFETs. The crystalline AlN films are grown by hot wall metal organic chemical vapor deposition (MOCVD) at 1100 °C. The amorphous Al 2 O 3 films are grown by repeated deposition and subsequent low temperature (200 °C) oxidation of thin Al layers using a hot plate. Our investigation shows a very low density of interface traps at the AlN/4H-SiC and the Al 2 O 3 /4H-SiC interface estimated from capacitance-voltage (CV) analysis of MIS capacitors. Current-voltage (IV) analysis shows that the breakdown electric field across the AlN or Al 2 O 3 is ∼ 3 MV/cm or ∼ 5 MV/cm respectively. By depositing an additional SiO 2 layer by plasma enhanced chemical vapor deposition at 300 °C on top of the AlN or Al 2 O 3 layers, it is possible to increase the breakdown voltage of the MIS capacitors significantly without having pronounced impact on the quality of the AlN/SiC or Al 2 O 3 /SiC interfaces.

Interface traps

AlN/4H-SiC interface

Al O /4H-SiC interface 2 3

MIS structure

Author

Rabia Y. Khosa

University of Iceland

University of Education

J. T. Chen

Linköping University

Michael Winters

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

K. Pálsson

University of Iceland

Robin Karhu

Linköping University

J. Hassan

Linköping University

Niklas Rorsman

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics, Microwave Electronics

Einar Sveinbjӧrnsson

Linköping University

University of Iceland

Materials Science in Semiconductor Processing

1369-8001 (ISSN)

Vol. 98 55-58

Subject Categories

Inorganic Chemistry

Materials Chemistry

Condensed Matter Physics

DOI

10.1016/j.mssp.2019.03.025

More information

Latest update

8/19/2019